摘要
XML模式和DTD(documenttypedefinition)规范化设计是给出一个很好地表示数据间依赖关系并消除了冗余的XML模式或DTD的集合.目前在这一方面开展的研究还不多,而且才刚起步.Provost提出将关系数据库理论应用于XML模式规范化设计的思想,这一思想还没有付诸实施.在Provost思想的基础上给出用于XML模式和DTD规范化设计的层次模式设计的算法.首先分析了基于Provost思想的层次分解;然后给出用于消除冗余模式的分解树设计算法;最后给出用于XML模式和DTD规范化设计的层次模式设计算法,这一算法克服了Provost思想的缺陷.相应于其他XML模式和DTD规范化设计的研究,在算法产生的层次模式中,完全MVD(multivalueddependency)和嵌入MVD的集合由给出的MVD集合导出;并且产生的层次模式具有消除冗余模式和满足无损联接的特性.
Normalization design of XML Schemas and DTDs (document type definitions) is to produce a set of XML schemas or DTDs that can well represent data dependencies and eliminate redundancies. Now there are a few researches on it, and the existing researches are still at its initial stage. Provost proposed the idea of applying the theory of relational database to XML schemas normalization design. This idea has not been put into practice. The paper shows algorithms of hierarchical schemas design for XML schemas and DTDs normalization design based on Provost抯 idea. Firstly the paper analyzes hierarchy decomposition based on Provost抯 idea. Then it presents an algorithm producing a decomposition tree to eliminate redundant schemas. Finally it shows an algorithm of hierarchical schemas design for XML schemas and DTDs normalization design to get over deficiencies for Provost抯 idea. With respect to other researches on normalization design for XML schemas and DTDs, the set of full and embedded MVDs in hierarchical schemas produced by these algorithms are implied by the given set of MVDs (multivalued dependencies), and the hierarchical schemas eliminate redundant ones and satisfy the lossless join property.
出处
《软件学报》
EI
CSCD
北大核心
2004年第7期1099-1106,共8页
Journal of Software
基金
国家自然科学基金
中国科学院软件研究所计算机科学实验室开放课题基金~~
